The present invention is directed to a method for reloading processor control programs that are loaded into a read only memory protected against erasing in processor-controlled apparatus and is directed to an arrangement for implementation of the method of the present invention.
Processor-controlled apparatus always requires a program for controlling the processor, generally referred to as software. In an apparatus that has a permanently prescribed set of functions to implement, as is often the case in EURO-SCOUT vehicle apparatus, this program is normally stored in a read-only memory, a program memory module such as, for example, RUMs, PROMs, EPROMs. Given changes due to technological progress or due to error corrections as well as given expansions of the scope of functions, it is often necessary or at least useful to modify this control program once or more after delivery of the apparatus. To this end, the microprocessor-controlled apparatus must usually be retrieved and opened in order to replace the program memory module.
Thus, for modification of the control program the prior art apparatus had to be centrally collected or opened at the place of employment for the appertaining memory modules to be replaced. When the memory modules were replaced in this manner the old modules had to be replaced by new modules. When the old modules were soldered into the circuit, the replacement could only ensue on the basis of cost-intensive unsoldering and soldering that are susceptible to error. Disadvantageously, such program modifications were avoided insofar as possible or only carried out in the most urgent cases because of the work outlay required for the purpose and the costs thus incurred.
It is an object of the present invention to provide a method and an arrangement that allow a processor control program or parts thereof to be input into a processor-controlled apparatus in a simple and fast manner without having to replace the program memory module.
In general terms the present invention is a method for reloading processor control programs that are loaded into a read only memory protected against erasing in processor-controlled apparatus. The loading ensues via a wireless data transmission interface. The processor-controlled apparatus is a mobile apparatus in which a loader is installed. This loader controls communication of the data transmission interface as well as the erasing and reprogramming of the read only memory. The processor control program to be reloaded or program parts (fragments) thereof are requested in blocks by the processor-controlled apparatus from a reloading station which likewise has a wireless data transmission interface. The processor-controlled program or the program parts is loaded into the read only memory. The individual program blocks are protected by check sums during the block-by-block transmission. After the end of the programming, the reloaded processor control program is checked by length comparison and check sum comparison to determine if the data transmission occurred error-free.
In an arrangement of the present invention for the implementation of the method of the present invention the reloading station is formed by a fixed station having a computer, having an interface and having a display means. The processor-controlled apparatus is formed by an on-board computer arranged in the vehicle and has an interface.
In the method of the present invention, the processor control program that is written in a read only memory protected against erasure in a program-controlled apparatus is rewritten via the wireless data transmission interface. The processor-controlled apparatus, which can be a mobile apparatus, has the loader provided for this purpose and a correspondingly fashioned program memory. The loader controls the communication of the data transmission interface as well as the erasure and reprogramming of the read only memory. The processor control program or a part thereof to be reloaded is requested block-by-block from a reloading station with a wireless data transmission interface, and is written in the read only memory. The individual program blocks are protected by check sums in the block-by-block transmission. After the end of the programming of the reloaded processor control program, a check to determine whether the data transmission occurred error-free is carried out on the basis of length comparison and check sum comparison.
The method of the present invention has the advantage that a new, improved or at least partially required control program can be written into the mobile, processor-controlled apparatus at suitable reloading stations without performing operations on the apparatus. For example, a plurality of program versions can be newly available, but a user of the processor-controlled apparatus requires only one of these programs. The reloading station therefore expediently offers the available programs or program versions. Information blocks are cyclically transmitted by means of which the available programs are recognized and can then be selected by the user or can be automatically selected by the apparatus. Advantageously, infrared light can be used as the transmission media.
The method of the present invention can be advantageously employed in a known traffic routing and information system (for example, EURO-SCOUT; see European reference EP 00 21 060). In this system the mobile apparatus which is usually installed in the vehicle is expediently informed of the presence of a reloading control program via transmission beacons of the known traffic routing and information system.
An arrangement which has a reloading station is provided for the implementation of the method of the present invention. This reloading station is formed by a fixed station a computer, a data transmission interface and a display means. The arrangement also has a processor-controlled apparatus in the form of an on-board computer that is located in the vehicle. A wireless data transmission interface is likewise arranged thereat.
Expediently, the reloading station is a one-lane drive-through station into which the vehicle drives and parks for the duration of the reloading.
In another expedient development of the present invention, the reloading station is a gas station, so that the program to be reloaded can also be written into the on-board computer while the tank of the vehicle is being filled.
In a further development of the present invention, the reloading station is a multi-lane drive-through station for the simultaneous reloading in a plurality of vehicles. It is especially advantageous in the arrangement of the present invention to use data transmission interfaces in the form of infrared interfaces of the known traffic routing and information system. In order to indicate the reloading event, display devices are provided in the reloading station. Alternatively, the display means present in the vehicle of a vehicle equipped for the known traffic routing and information system is used, whereby this display is transmitted into the vehicle from the loading station and displayed in the vehicle.
Instead of the specific reloading stations, is also possible to use infrared beacons of the traffic routing and information system for the reloading or rewriting of the control programs into the read only memories of the vehicle. In this embodiment the processor control program to be loaded is transmitted into the vehicle segment-by-segment, i.e., from beacon to beacon. This has the advantage that separate reloading stations are not required. The writing of a complete program, however, lasts longer than the normal contact time with a beacon, so that the control program to be reloaded is transmitted in sections, i.e., each part to a different beacon that the vehicle is momentarily passing.